Thomas a



(No Model.)

T. AQMAOAULAY.

TENSION RELEASE FOR SEWING MACHINES.

No. 273,562. Patented Mar-.6,1883.

N ITED STATES PATENT OFFICE.

THOMAS A. MAGAULAY, on NEW YORK, N. Y.

T ENSlON-RELEASE FOR SEWING-MACHINES.

SPECIFICATION forming partof Letters Patent No. 273,562, dated March 6,1833.

Application filed August 18, 1881. (No model.)

To all whom it may concern:

Be it known that I, THOMAS A. MAGAULAY, of the city, county, and Stateof New York, have invented an Improved Tension Device forSewing-Machines; and I do hereby declare that the lollowing is a fulland exact description thereof, reference being had to the accompanyingdrawings, making part of this specification.

ln removing the sewed fabric or article from asewing-machine. the usualpractice is, first, to pull 011' from the tension a sufficient length ofthread to enable the fabric to be withdrawn without drawingupon thethread, after which withdrawal to cut the thread. of pulling the threadagainst the force of the tension often breaks the thread, and if thefabric should be drawn any farther than the length of thread previouslyset free there is again aliability to break the thread. By my improvedtension device the tension may be released without strain or injury tothe tension-spring, thereby allowing the thread to be pulled freely fromthe spool while removing the fabric from the machine, and withoutbreakage.

In theaccompanyingdrawiugs,Figure 1 represents a side View of myimproved tension device as applied to the arm ofa sewing-machine; Fig.2, a similar view, butshowing the parts of the tension device inposition for releasing the tension, and thereby allowing the fabric tobe withdrawn from the machine without hinderance from thetensi'on andwithout liability to break the thread; Fig. 3, a top view, and Fig. 4 anunder side view, of the notched and 4 hinged tension-plate which formsone part of my invention; Fig. 5, a top view of the tensionplates andtheir adjuncts.

Like letters designate corresponding parts in all of the figures. I

Let A represent a portion of a sewing machine arm on which my improvedtension device is mounted. An upper spring or elastically-yieldingtension-plate, B, of any suitable form or construction, is secured to aboss or'projection, a, of the arm A by a thumbscrew, 0, the rear end ofsaid plate bearing on another boss or projection, b, of the arm, whilethe other end of the plate presses down upon a counter-plate, D, betweenwhich and the This operation in releasing the tension.

spring-plate the thread passes in the usual way, and is compressed withthe requisite force to produce the proper tension by the thumb-screw Gpressing down the middle of the plate, there being sufficient spacebetween the plate and the attaching-boss a to allow all the downwardcurvature and pressure ever required. The lower or counter plate, D, ishinged or pivoted to another projection, c, of the arm A by means ofcars or bearings ff, through which the pivot-pin 9 extends, as well asthrough theprojection c,as shown, or otherwise, in a suitable orequivalent manner. One of the ears or bearingsf is extended downward, asat d, (or a suitable projection otherwise extends down from the plate,)and is preferably bent round into a nearly horizontal 'POSltlOYl-, asshown, suitable for reaching to and moving by the hand of the operator.The forward edge of the plate D is suitably rounded or curved,assindicated, to allow the plate, as it is rocked on its pivot, to bearupward against the spring-plate B and lift it somewhat, as shown in Fig.2; and this edge of the plate D is notched, as shown in Figs. 3 and 4,at h, so that when the plate is turned into the position for lifting theplate 13, as shown in the said Fig. 2, the thread lying centrally overthe said plate D will be'in the notch thereof, and consequently beentirely free from pressure and tension, the adjacent pressure-surfacesof the two plates then being separated. Thus at the time no impedimentis offered to the drawing of the thread from its spool. On let ing gothe handle-projection d the springpressure of the upper plate, B,immediately brings back the two plates into parallelism andthread-compressing position, as shown in Fig. 1.-

In this as would be in any spring tensionrelcase it is important that alimit be placed to the extent to which the spring is retracted l haveeftected this purpose, and have represented, in connection with mytension-release, a stop, 1, which limits the downward movement of thehandle-lever d. Fig. 2 shows the said lever as depressed into contactwith the stop, and of course it cannot be depressed any farther, and sono undue strain can come on the spring-plate B.

Any unessential changes inthe foregoing construction may be made,provided the essential device and its proper operation be retained. Thisapplication is a renewal and direct continuance of a part of myapplication for improvements in sewing-machines filed March 8, 1880, No.4,539, and struck out of said application by amendment of-even'date withthe filing of this application, as required by the Gommissionersdecision.

What I claim as my invention, and desire to secure by Letters Patent,is-- 1. In a sewing-machine tension, the combination of apivoted notchedtension-plate, D, with a spring"counter-plate, B, and a suitable devicefor tilting the notched plate D to release the thread from tension,substantially as and for the purpose herein specified.

2. The combination of the pivoted notched tension-plate D, provided withthe handle-lever d, the counter-plate B, and screw 0, substantially asand for the purpose herein specified. 3. The combination of the pivotednotched tension -plate D, provided with a handle. d, spring:counter-plate B, and a stop, i, to limit the movement of the plate D,substantially as and for the purpose herein specified.

4. In combination with a counter-tension plate, B, a. pivoted or rockingtension-releasing plate, I), provided with ineans,in connection with thesaid counter-tension plate, for permitting the release of the thread,and with a handle for operating the said releasing-plate,

substantially as and for the purpose herein with means, in connectionwith the said counter-tension plate, for permitting the release of thethread, and with a handle for operating it to release the thread, forthe purpose Herein specified. p

7. in combination with acounter-tension device and a projection, c, thepivoted tensionplate, D, having a lever, d, for operating the plate torelease the thread, substantially as and for the purpose hereinspecified.

8. A lever tension-plate adapted for use with a counter-tensiondevicc,and having a handle for operating it to release the thread,substantially as and for the purpose herein specified.

9. In combination with a counter-tension device a lever tension-releaseplate and astop to limit the movement of the same, substantially as andfor the purpose herein specified.

10. A tension-release plate having wings ff and handle d, pivoted to asupport. 0, in combination with a counter-tension plate and regulatingdevice, substantially as and for the purpose herein specified.

11. In combination, a tension-release plate provided with ahandle-lever, a counterten sion plate, and a regulating device,substantially as and for the purpose herein specified.

12. [n a sewing-machine tension, the combination of a notched'tension-release plate with a counter-tension plate and a regulatingdevice, suhstantiallyas and for the purpose herein specified.

13. A tension-release adapted for use with THOS. A. MAOAU LAY.

Witnesses:

J. S. BROWN, D. P. UowL.

